Quenching and cutting oil composition



3,072,506 QUENCHHNG AND EUTTHNG OIL COMPOSITION Karl-Heinz Kopietz,Hildcsheim, Germany, assignor to Houghton-Cheniie Ganhii, Hildesheim,Germany No Drawing. Filed Apr. 11, 1958, Ser. No. 727,774 (Ilaimspriority, application Germany Apr. 13, 1957 2 Claims. (Cl. 148l8) Theinvention relates to quenching and cutting oils and more particularly tosuch oil compositions which are readily removed fronithc treated metalpieces by washing with Water.

Heretofore, the'water-insoluble quenching or cutting oils had to beremoved from the treated work pieces by means of hot alkaline solutionsor organic solvents.

This cleaning process is expensive and time consuming, andt hasfrequently been omitted even in cases where" is actually required. Itwould, therefore, be of great advantage if the cleaning procedure couldbe I cheape ned and simplified.

It is a principal object of the invention to provide cutting andquenching oil compositions which arereadily removable from the workpieces after treatment.

Other objects and advantages will be apparent from a consideration ofthe specification and claims.

According to the invention, oil compositions are used for quenching andcutting purposes which contain a heat stable non-ionic, non-saponifiable(saponification No. 5.2 polyethenoxy surfactant. Such surfactants arewell known and available in commerce under various tradenames, forinstance under the names Stokolan (Chemische Fabrik Stockhausen 8:Cie.), Emulphor and comprise for instance polyethenoxy ethers of fattyalcohols, such as those of hexyl alcohol, heptyl alcohol, dodecylalcohol, tetradecyl alcohol, oleic alcohol, stearic alcohol, andmixtures of such alcohols, and polyethenoxy esters. Particularly usefulare polyethenoxy alkyl phenols alone or in combination with otherpolyethenoxy compounds.

As alkyl phenol component, alkyl phenols having one or more alkyl groupsof about 6 to 18 C atoms may be used, for instance diamyl, p-tert.octyl, noyl phenol. I found particularly suitable polyethenoxyemulsifiers which are co-condensation-products of pure aliphatic andphenolsubstituted aliphatic glycols. The emulsifiers used must be eithercompletely or partially soluble in the oil or must be able to formstable suspensions. Preferably, they are incorporated in the oil eitherin the form of a molecular dispersion or in the form of a stablesuspension.

The emulsifier should be present in the oil in amounts of about 1 to 15,preferably 2 to percent by weight of the oil.

Stabilizers and inhibitors, for instance anti-oxidants, may be added inamounts of about 0.5 to 3 percent by weight to prevent decomposition ofthe emulsifiers. A suitable stabilizer is, for instance, oleyl alcohol.

When the recited emulsifiers are used, the oil film remaining on thesurface of the work pieces is readily removed by spraying with water orby dipping the work piece in water. The water temperature has noappreciable infiuence on the cleaning effect, and it is usuallysufiicient to use cold water. The cleaning effect is so good thatpractically no oil remains on the Work pieces, particularly if thepieces are sprayed with water. In dipcleaning, the water becomesenriched with oil and is eventually converted to an oil-in-wateremulsion. In this case, a thin oil film remains on the work piece afterevaporation of the water. In this way, it is possible either to obtain aclean completely oil-free surface on the work piece by spraying withwater, or to retain a fine, rustprotecting oil film by the dippingprocedure. Said film nit ttes Patent 0 is formed from the oil-in-wateremulsion and can be removed later by spraying.

The protection of the work pieces by a removable oil film makes itpossible to store the pieces for any length of time without risk of rustformation and to remove the oil film only shortly before tempering. Thispresents great advantages over the conventional cleaning procedure withvaporized chlorinated hydrocarbons (trichloroethylene,perchloroethylene) where the metal surface is rendered completely freeof oils and fats so as to make rusting unavoidable on storage.

The oils used as quenching and cutting oils are Well known to theskilled in the art. Any such oil may be combined with the recitedemulsifiers to form the waterremovable compositions of the invention.Instead of mineral oils, also other oily liquids may be used, which havequenching properties similar to mineral oils.

I have found that the addition of the recited emulsifier does notsubstantially affect the quenching effect of the oil. It is, therefore,possible to convert any oil having the desired quenching properties to awater-removable oil composition, which allows of-adopting the inventionin any plant without changing otherwise the type of oil used.

The following examples are given to illustrate the use of saidcompositions.

EXAMPLE 1 Hardening 0 Pinion Gear in F lame-Hardening Machines In theflame hardening of the gears of chain drives in a machine for hardeningthe perimeters of toothed wheels, a compound high duty quenching oil ofthe following composition is used.

Percent Refined spindle oil (viscosity 1.6 E./50 C. 87 High molecularresidue'from crude oil refining 8 Emulsifier 62082 of Chemische FabrikStockhausen & Cie., Krefeld (Germany) 4.5 Oleic alcohol (iodine number-85) .5

The product 62082 is a polyalkyleneglycol derivative consisting'of acombination-of a chain of'about 4 ethyleneglycol units with 'one2-phenyl-propyleneglycol unit each in terminal position. It has amolecular weight of about 465.

After hardening, the toothed wheels are washed in a container of coldwater. This procedure is considered particularly pleasant because theoperators have always clean hands and the gears are transferred tofurther processing in clean condition.

EXAMPLE .2

Thermal Refinement of Small Work Pieces Heretofore, punched and bentspring steel parts ofa thickness of about .5 mm. were hardened inquenching oil, which could not be rinsed olf withwater, and thentempered in .a circulating air oven. Prior to temperingthe springs werecleaned with chlorinated hydrocarbons. In this way, the surface Wascompletely freed from oil but the parts became sometimes rusty evenbefore tempering.

'[his drawback was eliminated by using a straight quenching oil of thefollowing composition:

Percent Refined spindle oil (viscosity 2.2 E./50 OleylpolyethyleneetherEmulphor P" of BASF Bad.

Anilin & Sodafabrik, Ludwigshafen (Rhine) 4.5

Oleylalcohol (iodine number 80-85) .5

After hardening the parts are washed in a shower of cold water and areplaced in the tempering oven. Over weekends, the hardened spring parts,which are wetted with the quenching oil, can be stored, whereby the oilfilm acts as anticorrosion agent. On the following Monday, the parts aretempered, whereby the oil film can be previously removed by washingwithout any difficulty.

EXAMPLE 3 Heat Treatment of Die-Forged Parts Heretofore, die-forgedparts were hardened in a compound high duty quenching oil 1.6 E./ 50 C.and subsequently without cleaning tempered in an air circulating oven.The heated oil naturally developed large amounts of obnoxious smoke. Theinflammable atmosphere formed in the oven was liable to producedangerous explosions.

According to the invention, the forged parts are hardened in awater-removable high duty compound quenching oil of the followingcomposition:

Percent Refined spindle oil, viscosity 2.2 E./50 C. 85 High molecularWeight residue from crude oil refining l Emulsifier 62082 of ChemischeFabrik Stockhausen & Cie. (Stokolan AW6) 4.5 Oleic alcohol (iodinenumber 80-85) .5

Subsequently, the parts were cleaned in water of about 60-80 C. Thecleaned parts are tempered without difliculty.

EXAMPLE 4 Induction Hardening of Cam Shafts From Pearlitic Castings forAutomobile Engines Refined spindle oil, viscosity 4.5 E./ 50 CEmulsifier 62082 of Chemische Fabrik Stockhausen & Cie 6 Oleylalcohol(iodine number 8085) 1 Rinsing the castings in water of about 40 C.removed the oil within a few seconds.

The invention is useful not only for quenching oils but also for cuttingoils, where also oils found suitable may be continued for use withaddition of the emulsifier.

EXAMPLE Hob Cutting of Key-Ways in Key Shafts Key shafts foragricultural machines made from soft annealed steel containing 0.15% C,1.2% Mn, and 1.1% Cr were heretofore milled with a cutting oil whichcould not be emulsified in water. Subsequently, the shafts were boredseveral times, whereby a boring oil emulsion was used. In order toprevent a contamination of the boring oil with the adhered cutting oil,the parts were cleaned between the two operations in a washing machinewith a hot alkaline solution.

According to the invention, said wash step can be eliminated by the useof a water-emulsifiable cutting oil of the following compositions:

Percent Refined mineral oil containing about 3.5% S (0.5%

After milling, the shafts were dipped in water of about 4 60 to 70 C. toremove the oil. every 8 hours.

After dipping, the work pieces are substantially clean, and nocontamination of the boring oil emulsion in the boring step is observed.In this way, the expensive washing operation is no longer necessary.

The used emulsifier is a condensation product of one mol nonyl phenolwith six moles ethylene oxide having a molecular weight of 484.

EXAMPLE 6 Thread Grinding In the procedure used before adoption of mynovel method, a conventional cutting oil available in commerce wasemployed for the thread grinding in a machine of the type built byLindner of Berlin-Whittenan, Germany. The material used was a steelcontaining 0.58% C, 1.20% Cr, 0.11% V, 0.80% Mn, which had been temperedto a Brinell hardness of 150 kg./mm.

In said procedure, the adhered grinding oil had to be removed in acleaning plant operated with orized chlorinated hydrocarbons. If thecleaning operation was omitted, the residual grinding oil frequentlyproduced corrosion, even though anticorrosion agents had been applied.

Such corrosion was effectively prevented when the same grinding oil wasused under the same conditions with an addition of 5 percent by weight,calculated on the oil, of the emulsifier 62082 of the compositionrecited in Example 1. Under these conditions, the oil was completelyremoved by spraying with cold water.

EXAMPLE 7 Gear Cutting of Bevel Gears for Automobiles The water isrenewed Bevel gears for automobiles made from a coarse grained annealedsteel containing 0.16% C, 1.1% M11 and 1.4% Cr were heretofore cut witha conventional oil, cleaned with trichloroethylene and coated with arustpreventing emulsion. The subsequent gas carburization was carriedout in conveyor ovens with a carrier gas containing small amounts ofpropane. In this operation, any residual oil on the gears had to beavoided because it would harmfully affect the gas atmosphere. For thisreason it was necessary to remove the rust-preventing oil in a washingplant.

By using a cutting oil composition according to the invention, it hasbecome possible to store the cut gears without the risk of corrosionuntil they were subjected to carburization. Immediately prior tocarburization, the gears were sprayed with clear warm water and passedfree from any oil films into the carburizing oven. This change of theprocedure to an emulsifier containing cut ting film resulted in aconsiderable simplification and economization of the process.

The used cutting oil had'the following composition:

Percent Mineral oil as in Example 5 88 Mixture of metal soaps, vegetableand animal oils 5 Rustproofing agent (Mersol-amino-acetate) 2 Emulsifieras in Example 5 4.5 Oleyl alcohol (iodine number -85) 0.5

Preferred emulsifiers are condensation products of an alkyl phenolcontaining an alkyl of 6 to 12 carbon atoms with 3 to 15 moles ofethylene oxide, especially condensation products of one mol of nonylphenol with six moles of ethylene oxide and of a mean molecular weightof 480 to 490.

I claim:

1. A method of heat treating steel parts comprising hardening said partsin a quenching oil consisting essentially of a mineral oil and about 1to 15 percent by weight of a condensation product of one mole of analkyl phenol containing an alkyl of 6 to 12 carbon atoms with 3 to 15moles of ethylene oxide as a nonionic nonsaponifiable emulsifier, andspraying ofi the quenched parts with water thereby completely removingadhered quenching oil.

2. The method as defined in claim 1 wherein said 5 emulsifier is thecondensation product of one mol of nonyl phenol with six moles ofethylene oxide having a mean molecular Weight of about 480 to 490.

References Cited in the file of this patent UNITED STATES PATENTS 62,681,315 Tongberg et. al. June 15, 1954 2,692,859 Talley et a1. Oct.26, 1954 2,857,301 Mauzy et al. Oct. 21, 1958 FOREIGN PATENTS 525,894Canada June 5, 1956 OTHER REFERENCES Pluronics in Cutting and GrindingFluids, pub. by

10 Wyandotte Chemicals Corp., Wyandotte, Mich., page 4,

January 1957.

Detergents, Wetting Agents, Emuls-ifiers, Brighteners, Sequestrants,Dyeing Assistants, Antara Chemicals Catalogue, No. AP-35, received inPat. Off. 1953, pp. 10-12.

D STATES PATENT OFFICE UNITE CERTIFICATE OF CORRECTION Patent N00 3 072506 January 8 1963 Karl-Heinz Kopietz e above numbered pator appears inth nt should read as rtified that err d Letters Pate It is hereby ce entrequiring correction and that the sai corrected below.

for "spraying" read washing =0 Column 5 line 2 25th day of June 1963;

sealed this Signed and (SEAL) Attest: ERNEST w. SWIDER DAVID L- LADDCommissioner of Patents Attestihg Officer

1. A METHOD OF HEAT TREATING STEEL PARTS COMPRISING HARDENING SAID PARTSIN A QUENCHING OIL CONSISTING ESSENTIALLY OF A MINERAL OIL AND ABOUT 1TO 15 PERCENT BY WEIGHT OF A CONDENSATION PRODUCT OF ONE MOLE OF ANALKYL PHENOL CONTANING AN ALKYL OF 6 TO 12 CARBON ATOMS WITH 3 TO 15MOLES OF ETHYLENE OXIDE AS A NONIONIC NONSAPONIFIABLE EMULSIFIER, ANDSPRAYING OFF THE QUENCHED PARTS WITH WATER THEREBY COMPLETELY REMOVINGADHERED QUENCHING OIL.